1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
|
/* Copyright 2015 greenbytes GmbH (https://www.greenbytes.de)
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef __mod_h2__h2_workers__
#define __mod_h2__h2_workers__
/* Thread pool specific to executing h2_tasks. Has a minimum and maximum
* number of workers it creates. Starts with minimum workers and adds
* some on load, reduces the number again when idle.
*
*/
struct apr_thread_mutex_t;
struct apr_thread_cond_t;
struct h2_mplx;
struct h2_request;
struct h2_task;
typedef struct h2_workers h2_workers;
struct h2_workers {
server_rec *s;
apr_pool_t *pool;
int next_worker_id;
int min_workers;
int max_workers;
int worker_count;
int idle_workers;
int max_idle_secs;
apr_size_t max_tx_handles;
apr_size_t spare_tx_handles;
unsigned int aborted : 1;
apr_threadattr_t *thread_attr;
APR_RING_HEAD(h2_worker_list, h2_worker) workers;
APR_RING_HEAD(h2_worker_zombies, h2_worker) zombies;
APR_RING_HEAD(h2_mplx_list, h2_mplx) mplxs;
int mplx_count;
struct apr_thread_mutex_t *lock;
struct apr_thread_cond_t *mplx_added;
struct apr_thread_mutex_t *tx_lock;
};
/* Create a worker pool with the given minimum and maximum number of
* threads.
*/
h2_workers *h2_workers_create(server_rec *s, apr_pool_t *pool,
int min_size, int max_size,
apr_size_t max_tx_handles);
/* Destroy the worker pool and all its threads.
*/
void h2_workers_destroy(h2_workers *workers);
/**
* Registers a h2_mplx for task scheduling. If this h2_mplx runs
* out of tasks, it will be automatically be unregistered. Should
* new tasks arrive, it needs to be registered again.
*/
apr_status_t h2_workers_register(h2_workers *workers, struct h2_mplx *m);
/**
* Remove a h2_mplx from the worker registry.
*/
apr_status_t h2_workers_unregister(h2_workers *workers, struct h2_mplx *m);
/**
* Set the amount of seconds a h2_worker should wait for new tasks
* before shutting down (if there are more than the minimum number of
* workers).
*/
void h2_workers_set_max_idle_secs(h2_workers *workers, int idle_secs);
/**
* Reservation of file handles available for transfer between workers
* and master connections.
*
* When handling output from request processing, file handles are often
* encountered when static files are served. The most efficient way is then
* to forward the handle itself to the master connection where it can be
* read or sendfile'd to the client. But file handles are a scarce resource,
* so there needs to be a limit on how many handles are transferred this way.
*
* h2_workers keeps track of the number of reserved handles and observes a
* configurable maximum value.
*
* @param workers the workers instance
* @param count how many handles the caller wishes to reserve
* @return the number of reserved handles, may be 0.
*/
apr_size_t h2_workers_tx_reserve(h2_workers *workers, apr_size_t count);
/**
* Return a number of reserved file handles back to the pool. The number
* overall may not exceed the numbers reserved.
* @param workers the workers instance
* @param count how many handles are returned to the pool
*/
void h2_workers_tx_free(h2_workers *workers, apr_size_t count);
#endif /* defined(__mod_h2__h2_workers__) */
|
